Bioaerosols are released in elevated quantities from composting facilities and are associated with negative health effects, although dose-response relationships are unclear. Exposure levels are difficult to quantify as established sampling methods are costly, time-consuming and current data provide limited temporal and spatial information. Confidence in dispersion model outputs in this context would be advantageous to provide a more detailed exposure assessment. We present the calibration and validation of a recognised atmospheric dispersion model (ADMS) for bioaerosol exposure assessments. The model was calibrated by a trial and error optimisation of observed Aspergillus fumigatus concentrations at different locations around a composting site. Validation was performed using a second dataset of measured concentrations for a different site. The best fit between modelled and measured data was achieved when emissions were represented as a single area source, with a temperature of 29 °C. Predicted bioaerosol concentrations were within an order of magnitude of measured values (1000–10,000 CFU/m3) at the validation site, once minor adjustments were made to reflect local differences between the sites (r2 > 0.7 at 150, 300, 500 and 600 m downwind of source). Results suggest that calibrated dispersion modelling can be applied to make reasonable predictions of bioaerosol exposures at multiple sites and may be used to inform site regulation and operational management.
|Number of pages||12|
|Journal||International Journal of Hygiene and Environmental Health|
|Publication status||Published - 1 Jan 2017|
Bibliographical noteFunding Information:
This work was jointly funded by the EPSRC and the Environment Agency through an industrial CASE award (EPSRC CASE award EP/G501319/1 ), and partly funded by the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Health Impact of Environmental Hazards at King’s College London in partnership with Public Health England (PHE) and collaboration with Imperial College London. The work of the UK Small Area Health Statistics Unit is funded by Public Health England as part of the MRC-PHE Centre for Environment and Health, funded also by the UK Medical Research Council. The authors would like to thank Patricia Bellamy for advice on statistical analysis. The views expressed are those of the authors and not necessarily those of the Environment Agency, EPSRC, the NHS, the NIHR, the Department of Health, Public Health England or the Medical Research Council.
© 2016 The Authors
- Aspergillus fumigatus